The IRS uses your prior year AGI (Adjusted Gross Income) to help verify your identity when you e-file. They no longer accept electronic filing PINs.
You can find your prior year AGI on: Form 1040: line 37, Form 1040A: line 21, or Form 1040 line 4.
Form 1040: line 37
Form 1040A: line 21
Form 1040EZ: line 4
If this is your first time filing taxes, you can enter “0” (this field can’t be blank). If you don't have last year's tax return, you can get your prior year AGI from the IRS.